Application of high frequency ejection ventilation-assisted one lung ventilation in minimally invasive thymectomy

Objective To study the role of high frequency ejection ventilation（HFJV）-assisted one lung ventilation（OLV） in minimally invasive thymectomy. Methods Thirty patients undergoing thymectomy with da Vinci S^TM surgical system and forty patients undergoing thymectomy with VATS were randomly divided into group A and group B（35 in each group）.After anesthesia,a left-sided double-lumen endotracheal tube was inserted.Patients in group A underwent HFJV for the right lung after OLV（f=60bpm,driving pressure=0.5kg/cm²）.Patients in group B received left-lung ventilation during operation.Blood gas was analyzed,Q_s/Q_t and lung compliance（C_dyn） were measured before OLV（T₁）,10 min（T₂）,30 min（T₃）,60min after OLV（T₄）,and 10min after double lung ventilation（T₅）,respectively. Results The PaO₂ and C_dyn were lower while the Q_s/Q_t and P_max were higher at T₁ than at T₂-T₄ in both groups（P＜0.05）.The PaO₂ was higher while the Q_s/Q_t was lower in group A than in group B（P＜0.05）.No significant difference was found in C_dyn and P_max between the two groups. Conclusion HFJV-assisted OLV can decrease the Q_s/Q_t and maintain a higher PaO₂ in patients undergoing minimally invasive thymectomy.